Overheating issues Q and A

My beloved 73 was stolen and wrecked. Thankfully, insurance is gonna come through. Before theft, I had the typical issue of climbing temp at idle. Quick rundown: WH 4 core triflow radiator, WH high flow water pump, Summit fixed (non-flex) high output fan, WH metal shroud, support core and airspaces around radiator sealed with rubber hose, 190 thermostat. Fan is spaced correctly in shroud and will pull papertowel THROUGH the radiator at 1500 RPM. Timing is good and 2bbl holley shows good color on the plugs (not too lean). I'm gonna have to replace the hood after the accident. Have any of you found that "scooped" hoods alow heat to exit the engine compartment as compared to stock ? I see that they offer vented inner wheel fenders, do these help ? All is well after I'm rolling it's just that damned prolonged idling in traffic and on the trail when real slow going. Not a big fan of flex fans. Never could get one to work well with the minimum clearances. I actually put one into the radiator, causing major carnage, after it measured with plenty of clearance (acording to manufacturer). Any further improvements need to be taken care of during this rebuild. I have considered a pusher electric, in addition,. As you know there are space problems but Spahl makes one that will fit with a high cfm. Whaddya think ?

We've got a High Country hood with the " cowl area " cut out .
At idle there is a lot of warm air coming out of the opening.
SHX

"will pull papertowel THROUGH the radiator at 1500 RPM"
your problem is at lower RPM, you need a fan that will pull more air at idle.
Maybe a smaller pully on the water pump or larger on the crank.
You should not have to add a pusher, its just a band aid.

What is your timing set at?

If you wanna know if you need to get air out run it with the hood off for a test run. Cutting the inner fender wells and a hood scoop with holes to exit air was a huge help for me. Is your gauge correct?

I realize that my problem is at lower RPM. above 1000 rpm the high cfm, fixed blade fan makes huge noise. I'll check into the smaller pulley. At least that won't effect my idle settings. my guage is correct. the problem only occurs at idle for long periods in high temp. Did you do the hood / fender mods one at a time or at the same time to see where the payoff was ? If running a "scooped" hood, are you running the hood with the scoop to the rear (my preferance) or in the front. It seams to me the front scoop would suck rain, etc. while driving

Did the hood and the fenders at the same time. The scoop has holes on the side and the back is cut out.

where is your temp sender located?

I've looked at the hoods available from Wild Horses. I'm only running a 289 (plenty for my purposes) and not real crazy about the looks of the fiberglass hoods offered. Maybe it's function over form as a rule. My mechanical temp. sendiing unit is in the stock 2bbl manifold near the front left (drivers side). N ever thought that wold matter much. But then again.....

Reason why I asked because my sender was in the back of the manifold (Victor JR) and I was fighting a heating issue for a year and never had a heating issue. The circulation in the area it was in was not enough to get the temp to come down for some reason. As soon as i moved it forward I was at 190 degree all day. I do have the cowl hood but may never had needed it.
What temps are you getting sitting and cruising?

Cutting out the inner fenders really helped me. I'm running headers and the heat just simply had no where to go.

ransil said:

What is your timing set at?

Click to expand...

This was one of my overheating problems - too advanced. In fact this may have been my biggest contributor to heat. I retarded my timing a bit and have been running 20 - 30 degrees cooler even on slow trails.